Encoder system

Abstract

A structure and associated method to accurately read an encoder tape in an encoder system. The encoder system comprises, a read head, a shoe structure adjacent the read head, and an encoder tape. The encoder tape is adapted to be read by the read head. The shoe structure is adapted to locally support the encoder tape and locally dampen a vibration of the encoder tape as the encoder tape is read by the read head.

1. An encoder system comprising:
 a read head; 
 a shoe structure adjacent the read head; and 
 an encoder tape positioned to be read by the read head at a local area, 
 wherein the encoder tape is secured at least at a first end and at a second end, and
 wherein the encoder tape is only locally supported by the shoe structure at the local area, and further wherein a vibration of the encoder tape is only locally dampened by the shoe structure at the local area, as the encoder tape is read by the read head. 
 
 
   
   
     2. The encoder system of  claim 1 , wherein said dampening comprises locally maintaining the encoder tape in a constant plane as the encoder tape is read by the read head. 
   
   
     3. The encoder system of  claim 1 , wherein the encoder system is adapted to control a spatial position of at least one positioning system. 
   
   
     4. The encoder system of  claim 3 , wherein the at least one positioning system is mounted in a pick and place machine. 
   
   
     5. The encoder system of  claim 1 , wherein the shoe structure comprises at least one smooth convex surface to dampen the vibration of the encoder tape as the encoder tape is read by the read head. 
   
   
     6. The encoder system of  claim 1 , wherein the shoe structure comprises at least one roller bearing to dampen the vibration of the encoder tape as the encoder tape is read by the read head. 
   
   
     7. The encoder system of  claim 1 , wherein the shoe structure comprises at least one air bearing to dampen the vibration of the encoder tape as the encoder tape is read by the read head. 
   
   
     8. The encoder system of  claim 1 , wherein the encoder tape extends laterally. 
   
   
     9. The encoder system of  claim 8 , wherein the encoder tape is at least 2 feet long. 
   
   
     10. The encoder system of  claim 1 , wherein the encoder tape is bonded to a metal strip adapted to act as a stiffener for the encoder tape. 
   
   
     11. A method comprising:
 providing an encoder system comprising, a read head, a shoe structure adjacent the read head, and an encoder tape; 
 securing the encoder tape at least at a first end and at a second end; 
 reading by the read head, the encoder tape at a local area; 
 only locally supporting by the shoe structure at the local area, the encoder tape as the encoder tape is read by the read head; and 
 only locally dampening by the shoe structure at the local area, a vibration of the encoder tape as the encoder tape is read by the read head. 
 
   
   
     12. The method of  claim 11 , wherein said dampening comprises locally maintaining the encoder tape in a constant plane as the encoder tape is read by the read head. 
   
   
     13. The method of  claim 11 , further comprising controlling by the encoder system, a spatial position of at least one positioning system. 
   
   
     14. The method of  claim 13 , further comprising:
 providing a pick and place machine; and 
 using by the pick and place machine, the at least one positioning system. 
 
   
   
     15. The method of  claim 11 , wherein the shoe structure comprises at least one smooth convex surface to locally dampen the vibration of the encoder tape as the encoder tape is read by the read head. 
   
   
     16. The method of  claim 11 , wherein the shoe structure comprises at least one roller bearing to locally dampen the vibration of the encoder tape as the encoder tape is read by the read head. 
   
   
     17. The method of  claim 11 , wherein the shoe structure comprises at least one air bearing to locally dampen the vibration of the encoder tape as the encoder tape is read by the read head. 
   
   
     18. The method of  claim 11 , wherein the encoder tape extends laterally. 
   
   
     19. The method of  claim 18 , wherein the encoder tape is longer than at least 2 feet long. 
   
   
     20. The method of  claim 11 , wherein the encoder tape is bonded to a metal strip adapted to act as a stiffener for the encoder tape.